- ID:
- ivo://CDS.VizieR/J/AJ/132/1256
- Title:
- eim BATC photometry of OJ 287
- Short Name:
- J/AJ/132/1256
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of our optical monitoring of the BL Lacertae object OJ 287 during the first half of 2005. The source did not show large-amplitude variations during this period and was in a relatively quiescent state. A possible period of 40 days was derived from its light curves in three BATC wave bands. A bluer-when-brighter chromatism was discovered, which is different from the extremely stable color during the outburst in 1994-1996. The different color behaviors imply different variation mechanisms in the two states. We then revisited the optical data on OJ 287 from the OJ-94 project and also found a probable period of 40 days in its optical variability during the late 1994 outburst. The results suggest that two components contribute to the variability of OJ 287 during its outburst state. The first component is the normal blazar variation. This component has an amplitude similar to that of the quiescent state and also may share a similar periodicity. The second component can be taken as a "low-frequency modulation" to the first component. It may be induced by the interaction of the assumed binary black holes in the center of this object. The 40 day period may be related to the helical structure of the magnetic field at the base of the jet or to the orbital motion close to the central primary black hole.
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- ID:
- ivo://CDS.VizieR/J/A+A/456/881
- Title:
- EIS: infrared deep public survey
- Short Name:
- J/A+A/456/881
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper is part of the series presenting the final results obtained by the ESO Imaging Survey (EIS) project. It presents new J and Ks data obtained from observations conducted at the ESO 3.5m New Technology Telescope (NTT) using the SOFI camera. These data were taken as part of the Deep Public Survey (DPS) carried out by the ESO Imaging Survey program, significantly extending the earlier optical/infrared EIS-DEEP survey presented in a previous paper of this series. The DPS-IR survey comprises two observing strategies: shallow Ks observations providing nearly full coverage of pointings with complementary multi-band (in general UBVRI) optical data obtained using ESO's wide-field imager (WFI) and deeper J and Ks observations of the central parts of these fields. Currently, the DPS-IR survey provides a coverage of roughly 2.1 square degrees (~300 SOFI pointings) in Ks with 0.63 square degrees to fainter magnitudes and also covered in J, over three independent regions of the sky. The goal of the present paper is to briefly describe the observations, the data reduction procedures, and to present the final survey products which include fully calibrated pixel-maps and catalogs extracted from them. The astrometric solution with an estimated accuracy of <0.15" is based on the USNO catalog and limited only by the accuracy of the reference catalog. The final stacked images presented here number 89 and 272, in J and Ks, respectively, the latter reflecting the larger surveyed area. The J and Ks images were taken with a median seeing of 0.7" and 0.8". The images reach a median 5 sigma limiting magnitude of J_AB~23.06 as measured within an aperture of 2", while the corresponding limiting magnitude in Ks_AB is ~21.41 and ~22.16mag for the shallow and deep strategies. Although some spatial variation due to varying observing conditions is observed, overall the observed limiting magnitudes are consistent with those originally proposed. The quality of the data has been assessed by comparing the measured magnitude of sources at the bright end directly with those reported by the 2MASS survey and at the faint end by comparing the counts of galaxies and stars with those of other surveys to comparable depth and to model predictions. The final science-grade catalogs together with the astrometrically and photometrically calibrated co-added images are available at CDS.
- ID:
- ivo://CDS.VizieR/J/A+A/452/119
- Title:
- EIS: infrared observations of CDF-S and HDF-S
- Short Name:
- J/A+A/452/119
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents infrared data obtained from observations carried out at the ESO 3.5m New Technology Telescope (NTT) of the Hubble Deep Field South (HDF-S) and the Chandra Deep Field South (CDF-S). These data were taken as part of the ESO Imaging Survey (EIS) program, a public survey conducted by ESO to promote follow-up observations with the VLT. In the HDF-S field the infrared observations cover an area of ~53 square arcmin, encompassing the HST WFPC2 and STIS fields, in the JHKs passbands. The seeing measured in the final stacked images ranges from 0.79" to 1.22" and the median limiting magnitudes (AB system, 2" aperture, 5sigma detection limit) are J_AB~23.0, H_AB~22.8 and K_AB~23.0mag. Less complete data are also available in JKs for the adjacent HST NICMOS field. For CDF-S, the infrared observations cover a total area of ~100 square arcmin, reaching median limiting magnitudes (as defined above) of J_AB~23.6 and K_AB~22.7mag. For one CDF-S field H-band data are also available. This paper describes the observations and presents the results of new reductions carried out entirely through the un-supervised, high-throughput EIS Data Reduction System and its associated EIS/MVM C++-based image processing library developed, over the past 5 years, by the EIS project and now publicly available. The paper also presents source catalogs extracted from the final co-added images which are used to evaluate the scientific quality of the survey products, and hence the performance of the software. This is done comparing the results obtained in the present work with those obtained by other authors from independent data and/or reductions carried out with different software packages and techniques.
- ID:
- ivo://CDS.VizieR/J/A+A/462/553
- Title:
- EIS: optical deep public survey
- Short Name:
- J/A+A/462/553
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents new five passbands (UBVRI) optical wide-field imaging data accumulated as part of the DEEP Public Survey (DPS) carried out as a public survey by the ESO Imaging Survey (EIS) project. Out of the 3 square degrees originally proposed, the survey covers 2.75 square degrees, in at least one band (normally R), and 1.00 square degrees in five passbands. The median seeing, as measured in the final stacked images, is 0.97", ranging from 0.75" to 2.0". The median limiting magnitudes (AB system, 2" aperture, 5{sigma} detection limit) are U_AB_=25.65, B_AB_=25.54, V_AB_=25.18, R_AB_=24.8 and I_AB_=24.12mag, consistent with those proposed in the original survey design. The paper describes the observations and data reduction using the EIS Data Reduction System and its associated EIS/MVM library. The quality of the individual images were inspected, bad images discarded and the remaining used to produce final image stacks in each passband, from which sources have been extracted. Finally, the scientific quality of these final images and associated catalogs was assessed qualitatively by visual inspection and quantitatively by comparison of statistical measures derived from these data with those of other authors as well as model predictions, and from direct comparison with the results obtained from the reduction of the same dataset using an independent (hands-on) software system. Finally to illustrate one application of this survey, the results of a preliminary effort to identify sub-mJy radio sources are reported. To the limiting magnitude reached in the R and I passbands the success rate ranges from 66 to 81% (depending on the fields).
- ID:
- ivo://CDS.VizieR/J/MNRAS/351/1290
- Title:
- ELAIS: final band-merged catalogue
- Short Name:
- J/MNRAS/351/1290
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog represents the final band-merged European Large-Area ISO Survey (ELAIS) Catalogue at 6.7, 15, 90 and 175{mu}m, and the associated data at U, g', r', i', Z, J, H, K and 20cm. Details about the origin of the survey, the observations, data reduction and optical identification are described in the paper. In addition to fluxes in the radio, infrared and optical passbands, spectroscopic redshifts are tabulated, where available. For the N1 and N2 areas, the Isaac Newton Telescope ugriz Wide Field Survey permits photometric redshifts to be estimated for galaxies and quasars.
- ID:
- ivo://CDS.VizieR/J/A+A/379/798
- Title:
- ELAIS H{alpha} emitting galaxies
- Short Name:
- J/A+A/379/798
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have carried out a survey searching for H{alpha} emitting galaxies at z~0.24 using a narrow band filter tuned with the redshifted line. The total sky area covered was 0.19 square degrees within the redshift range 0.228 to 0.255 in a set of four fields in the ELAIS-N1 zone. This corresponds to a volume of 9.8x10^3^Mpc^3^ and a look-back time of 3.6Gyr when H=50km/s/Mpc and q=0.5 are assumed. A total of 52 objects are selected as candidates for a broad band limiting magnitude of I~22.9, plus 16 detected only in the narrow band image for a narrow band limiting magnitude for object detection of 21.0. The threshold detection corresponds to about 20{AA} equivalent width with an uncertainty of ~+/-10{AA}. Point-like objects (15) were excluded from our analysis using CLASS_STAR parameter from SExtractor. The contamination from other emission lines such as [O II]{lambda}3727, H{beta} and [OIII]{lambda}{lambda}4959,5007 at redshifts 1.2, 0.66 and 0.61 respectively is estimated, and found to be negligible at the flux limits of our sample. We find an extinction-corrected H{alpha} luminosity density of (5.4+/-1.1)x10^39^erg/s/Mpc^3^. Our survey for H{alpha} emitting galaxies was carried out using the focal reducer CAFOS at the 2.2 m telescope in CAHA (Centro Astronomico Hispano-Aleman, Almeria, Spain). This instrument is equipped with a 2048x2048 Site#1d CCD with 24{mu}m pixels (0.53" on the sky), which covers a circular area of 16'diameter.
- ID:
- ivo://CDS.VizieR/J/AJ/130/1111
- Title:
- Elemental abundances of field red giants
- Short Name:
- J/AJ/130/1111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We summarize a selection process to identify red giants in the direction of the southern warp of the Galactic disk, employing VI_C_ photometry and multi-object spectroscopy.
- ID:
- ivo://CDS.VizieR/J/AJ/159/46
- Title:
- Elemental abundances of 416 stars in 5 dSphs of M31
- Short Name:
- J/AJ/159/46
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep spectroscopy from Keck/DEIMOS (DEep Imaging Multi-Object Spectrograph) of Andromeda I, III, V, VII, and X, all of which are dwarf spheroidal satellites (dSphs) of M31. The sample includes 256 spectroscopic members across all five dSphs. We confirm previous measurements of the velocity dispersions and dynamical masses, and we provide upper limits on bulk rotation. Our measurements confirm that M31 satellites obey the same relation between stellar mass and stellar metallicity as Milky Way (MW) satellites and other dwarf galaxies in the Local Group. The metallicity distributions show trends with stellar mass that are similar to those of MW satellites, including evidence in massive satellites for external influence, like pre-enrichment or gas accretion. We present the first measurements of individual element ratios, like [Si/Fe], in the M31 system, as well as measurements of the average [{alpha}/Fe] ratio. The trends of [{alpha}/Fe] with [Fe/H] also follow the same galaxy mass-dependent patterns as MW satellites. Less massive galaxies have more steeply declining slopes of [{alpha}/Fe] that begin at lower [Fe/H]. Finally, we compare the chemical evolution of M31 satellites to M31's Giant Stellar Stream and smooth halo. The properties of the M31 system support the theoretical prediction that the inner halo is composed primarily of massive galaxies that were accreted early. As a result, the inner halo exhibits higher [Fe/H] and [{alpha}/Fe] than surviving satellite galaxies.
- ID:
- ivo://CDS.VizieR/J/other/IBVS/5542
- Title:
- Elements of southern eclipsing binaries
- Short Name:
- J/other/IBVS/554
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A set of 442 eclipsing binaries was selected from the GCVS catalog (Kholopov et al., 2003) that had declination <0{deg}, minimum magnitude brighter than 13.0, and no published times of minima later than JD 2440000 available through the NASA ADS service. An automated web-based data gathering application was developed to retrieve and display data from the ASAS-3 database (Pojmanski, 2002, Cat. J/AcA/48/35>). A search radius of 45 arcsec was used when selecting candidate stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/693/617
- Title:
- Ellipticities of cluster early-type galaxies
- Short Name:
- J/ApJ/693/617
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have compiled a sample of early-type cluster galaxies from 0<z<1.3 and measured the evolution of their ellipticity distributions. Our sample contains 487 galaxies in 17 z>0.3 clusters with high-quality space-based imaging and a comparable sample of 210 galaxies in 10 clusters at z<0.05. We select early-type galaxies (elliptical and S0 galaxies) that fall within the cluster R_200_, and which lie on the red-sequence in the magnitude range -19.3>M_B_>-21, after correcting for luminosity evolution as measured by the fundamental plane.
